# 02 - Problems involving sum of two numbers

**Problem 3**

A man bought a cellphone and laptop for P50,000.00, paying three times as much for the laptop as for the cellphone. How much did each cost?

**Solution 3**

Let

3

P12,500.00 = cost of cellphone

P37,500.00 = cost of laptop

*x*= amount paid for the cellphone3

*x*= amount paid for the laptop$x + 3x = 50\,000$

$4x = 50\,000$

$x = 12\,500$

$3x = 37\,500$

Answer:

P37,500.00 = cost of laptop

**Problem 4**

Two boys, counting their money, found that together they had P372, and that Rody had ﬁve times as much as Mar. How much had each?

**Solution 4**

Let

5

P62 = money of Mar

P310 = money of Rody

*x*= money of Mar5

*x*= money of Rody$x + 5x = 372$

$6x = 372$

$x = 62$

$5x = 310$

Answer

P310 = money of Rody